Are you fit enough to save your brain?

George Bernard Shaw famously quipped that “youth is wasted on the young”… and the same may be true for physical fitness. Take a look inside most gyms and you’ll see lots of young, fit people exercising vigorously, but as they get into their 40s and beyond, most people’s workouts have wound down considerably in intensity and frequency… or disappeared altogether.

According to a recently-published study on cardiovascular fitness and dementia, that’s a BIG mistake – the higher your level of physical fitness in midlife, the lower your risk of losing your marbles as you get older.

The study began in 1968, when 1462 Swedish women aged between 38 and 60 were recruited for the Prospective Population Study of Women (PPSW), a long-running epidemiological study which has examined many factors affecting health and survival.

191 of these women participated in a cardiovascular fitness test which consisted of riding an exercise bike, with progressively increasing resistance, until they reached exhaustion. On the basis of their performance, the women were then classified into 3 categories: low, medium and high fitness.

Over the next several decades, the researchers administered periodic neuropsychiatric examinations to the women, and also used Sweden’s highly-centralised medical record-keeping system to track how many of them developed dementia. 23% of the women developed dementia within the follow-up period from 1968 to 2012.

But after adjusting for confounders (other factors such as age, education level, cigarette smoking, wine consumption, high blood pressure and diabetes, which are all known to affect dementia risk), a startling difference emerged: 32% of women with low fitness in midlife developed dementia, while 25% with medium fitness and only 5% with high fitness did so. Of those whose fitness was so low that they couldn’t continue the cycling test past the warm-up phase, a horrifying 45% became demented.

And those with high fitness who did develop dementia were, on average, 11 years older than those with medium fitness who become demented.

Compared to women with medium fitness, those with high fitness were 88% less likely to develop dementia, while those with low fitness were 41% more likely.

While it’s not yet clear exactly why a high level of fitness protects against dementia, the researchers point out that being fit reduces the risk of high blood pressure, high cholesterol, obesity and diabetes, all of which are known to contribute to dementia. It also enhances neurotransmitter production and neurogenesis (growth of new brain cells) and formation of new connections between existing brain cells, which protect against dementia.

Of course, this is an observational study and hence can only show an association between fitness and dementia risk, not a causal link. No one can yet claim that being fit in midlife will protect you against developing dementia.

On the other hand, what’s the downside of improving your fitness level? If you ramp up the frequency and intensity of your exercise sessions (under the guidance of an exercise physiologist or well-trained personal trainer, if you have any injuries or medical history that necessitates caution), you’re going to look, feel and function better in every way.

My husband works out 5-6 times per week at the local YMCA. At almost 64, he’s proud that his aerobic fitness and muscle strength are higher than they have been in his entire life, thanks to the fact that he now takes better and more consistent care of himself than when he was younger.

But every time he comes home from the gym, he regales me with his observations of other gym-goers who aren’t doing quite so well. The YMCA runs exercise programs for seniors which consist of mild aerobic activity, light weights workouts and gentle stretching, presumably designed for people who haven’t put their bodies through their paces in any serious fashion for a good many years, as well as people who are recovering from a heart attack, joint surgery or other health problem or injury.

Unfortunately, in my husband’s observation, there seems to be next to no progression built into these programs, and consequently the people participating in them never seem to get any fitter. Many middle-aged and older people seem to be frightened of exerting themselves to any serious degree, but provided there are no medical contraindications to intense exercise, and they receive proper instruction to avoid injury and ramp up their exercise intensity in a stepwise fashion, the risk of harm is incredibly low.

I don’t know about you, but I’m more afraid of developing dementia than I am of breaking a sweat! If pushing myself out of my comfort zone to improve my fitness is the price I need to pay to keep my brain healthy as I get older, I’m more than happy to pay it… especially since, like my husband, I’ve found that I’m fitter and stronger now at 46 than I’ve been in my entire life, which is quite a thrill.

The bottom line: any exercise is better than none at all, but if you want maximum protection against dementia, you probably need to do more than take a gentle daily stroll. Find an activity that you enjoy that lends itself to ramping up the intensity over time, and a fitness professional to coach you if you need it. Your body will thank you for it, and so will your brain.

Does dementia run in your family? Do you want to know what you can do to minimise your risk? Apply for a Roadmap to Optimal Health Consultation today to develop a comprehensive dementia prevention program that’s tailored to your unique situation.